9003

• https://docs.optimism.io/builders/node-operators/configuration/base-config

The default port for the peer-to-peer network is 9003. Is need to open this port on your firewall to receive unsubmitted blocks. For your node to be discoverable, this port must be accessible via both TCP and UDP protocols.

Related

• p2p

See also

• op-node [ networks dump-rollup-config], 9003
• p2p, The Bitcoin P2P Network Library, Libbitcoin, bx, DHT